The Prediction of Water Activities in Multicomponent Systems

  • Terence H. Lilley
  • Robin L. Sutton
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 302)

Abstract

The molecular bases of the equilibrium water activity concept are discussed and illustrated using some simplified examples. It is shown, using a relatively refined treatment, that at the moment we are not in a position to predict water activities, even for simple systems. A method is described which allows the prediction of the water activity of multicomponent systems from the properties of solutions containing one and two solutes. The method can also be used to predict solubilities in systems containing more than one solute, and this is illustrated with an example.

Keywords

Activity Coefficient Water Activity Hydration Number Osmotic Coefficient Amino Acid Amide 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    K. Nelander, G. Olofsson, G.M. Blackburn, H.E. Kent, and T.H. Lilley, Aqueous solutions containing amino acids and peptides. Part 18. The enthalpy of solution of N-acetyl-L-phenylalaninamide in aqueous solutions containing formamide, Thermochimiea Acta 78:303 (1984).CrossRefGoogle Scholar
  2. 2.
    P.J. Flory, Thermodynamics of high-polymer solutions, J. Chem. Phys. 9:660 (1941).CrossRefGoogle Scholar
  3. 3.
    M.L. Huggins, Solutions of long-chain compounds, J. Chem. Phys. 9:440 (1941).CrossRefGoogle Scholar
  4. 4.
    R.H. Stokes and R.A. Robinson, Solvation equilibria in very concentrated electrolyte solutions, J. Solution Chem. 2:173 (1973).CrossRefGoogle Scholar
  5. 5.
    W.G. McMillan and J.E. Mayer, The statistical thermodynamics of multicomponent systems, J. Chem. Phys. 13:276 (1945).CrossRefGoogle Scholar
  6. 6.
    See for example, T.H. Lilley, Physical properties of amino acid solutions, In: “The Chemistry and Biochemistry of the Amino Acids,” G.C. Barrett, ed., Chapman and Hall, London (1985).Google Scholar
  7. 7.
    G.M. Blackburn, T.H. Lilley, and E. Walmsley, Aqueous solutions containing amino acids and peptides. Part 13. Enthalphy of dilution and osmotic coefficients of some Af-acetyl amino acid amides and some N-acetyl peptide amides at 298.15 K, J. Chem. Soc. Faraday Trans. 1 78:1641 (1982).CrossRefGoogle Scholar
  8. 8.
    T.H. Lilley, Criticism of a proposed corrected form of the Ross equation and a suggested extension of the equation, Int. J. Food Sci. Technol. 22:563 (1987).CrossRefGoogle Scholar
  9. 9.
    R.H. Stokes and R.A. Robinson, Interactions in aqueous nonelectrolyte solutions. I. Solute-solvent equilibria, J. Phys. Chem. 70:2126 (1966).CrossRefGoogle Scholar
  10. 10.
    K.D. Ross, Estimation of water activity in intermediate moisture foods, Food Technol. 29:26 (1975).Google Scholar
  11. 11.
    C.C. Briggs, R. Charlton, and T.H. Lilley, The osmotic coefficients of HClO4 — LiClO4 — NaClO4 mixtures, J. Chem. Thermodynamics 5:445 (1973).CrossRefGoogle Scholar
  12. 12.
    See R.A. Robinson and R.H. Stokes, Activity coefficients in aqueous solutions of sucrose, mannitol and their mixtures at 25°C, J. Phys. Chem. 65:1954 (1961) for the references to earlier work.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Terence H. Lilley
    • 1
  • Robin L. Sutton
    • 1
  1. 1.Department of ChemistryThe UniversitySheffieldUK

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